by [baɪ]
When by is the second element in a phrasal verb, eg go by, stand by, look up the verb. When it is part of a set combination, eg by chance, by degrees, by half, look up the other word.
preposition
1 (close to) al lado de; junto a
the house by the church la casa que está al lado de or junto a la iglesia; come and sit by me ven y siéntate a mi lado or junto a mí; I've got it by me lo tengo a mi lado; "where's the bank?" — "it's by the post office" —¿dónde está el banco? —está al lado de or junto a la oficina de correos
the house by the river la casa que hay junto al río; a holiday by the sea unas vacaciones en la costa
2 (via) por
he came in by the back door/by the window entró por la puerta de atrás/por la ventana; which route did you come by? ¿por dónde or por qué camino or por qué ruta viniste?; I went by Dover fui por Dover
3 (past) por delante de
she walked by me pasó por delante de mí; he rushed by me without seeing me pasó deprisa por delante de mí sin verme; we drove by the cathedral pasamos con el coche por delante de la catedral
4 (during)
by day de día; by night de noche; by day he's a bank clerk and by night he's a security guard de día es un empleado de banco y de noche es guarda de seguridad; a postcard of London by night una postal nocturna de Londres
5 (in expressions of time) (not later than) para
we must be there by four o'clock tenemos que estar allí para las cuatro; can you finish it by tomorrow? ¿puedes terminarlo para mañana?; I'll be back by midnight estaré de vuelta antes de or para la medianoche; applications must be submitted by 21 April las solicitudes deben presentarse antes del 21 de abril
by the time I got there it was too late cuando llegué ya era demasiado tarde
it'll be ready by the time you get back estará listo para cuando regreses
by that time or by then I knew para entonces ya lo sabía
(in year, on date, on day) by tomorrow/Tuesday, I'll be in France mañana/el martes ya estaré en Francia; by yesterday it was clear that ... ayer ya se veía claro que ...; by 30 September we had spent £500 a 30 de septiembre habíamos gastado 500 libras; by 1998 the figure had reached ... en 1998 la cifra había llegado a ...; by 2010 the figure will have reached ... hacia el año 2010 la cifra habrá llegado a ...
6 (indicating amount or rate)
to reduce sth by a third reducir algo en una tercera parte; to rent a house by the month alquilar una casa por meses; letters were arriving by the sackload las cartas llegaban a montones; it seems to be getting bigger by the minute/day parece que va creciendo minuto a minuto/día a día
to sell sth by the dozen vender algo por docenas
we get paid by the hour nos pagan por horas
we sell by the kilo vendemos por kilos
we charge by the kilometre cobramos por kilómetro
little by little poco a poco
one by one uno tras otro; uno a uno
two by two de dos en dos
7 (indicating agent, cause) por
the thieves were caught by the police los ladrones fueron capturados por la policía; la policía capturó a los ladrones; surrounded by enemies rodeado de enemigos; a painting by Picasso un cuadro de Picasso; who's that song by? ¿de quién es esa canción?; he had a daughter by his first wife tuvo una hija con su primera mujer
8 (indicating transport, method etc)
by air [+travel] en avión; [+send] por avión; por vía aérea
by bus/car en autobús/coche
to pay by cheque pagar con cheque
made by hand hecho a mano
by land por tierra
by the light of the moon/a candle a la luz de la luna/de una vela
by rail or train en tren
by sea por mar
9 (with gerund)
by working hard a fuerza de mucho trabajar; trabajando mucho; he ended by saying that ... terminó diciendo que ...
10 (according to) según
by my watch it's five o'clock según mi reloj son las cinco; by my calculations según mis cálculos
to call sth by its proper name llamar algo por su nombre; it's all right by me por mí no hay problema or está bien; if that's okay by you si no tienes inconveniente
11 (measuring difference)
she missed the plane by a few minutes perdió el avión por unos minutos; we beat them to Joe's house by five minutes llegamos a casa de Joe cinco minutos antes que ellos; broader by a metre un metro más ancho
she's lighter than her brother by only a couple of pounds pesa solo un par de libras menos que su hermano; it's too short by a metre es un metro más corto de lo que tendría que ser; it missed me by inches no me dio por un pelo; me pasó rozando
12 (in measurements, sums)
a room 3 metres by 4 una habitación de 3 metros por 4
to divide by dividir por or entre
to multiply by multiplicar por